Gas burner



April 29, 1952 R. B. PLASS ET AL GAS BURNER 3 Sheets-Sheet 1 Filed Aug. 13, 1949 INVENTORS RAYMOND 31 L455 EDWARD M B/IVGHA/W BY 2! ATTORNEY April 29, 1952 R. B. PLASS ET AL 2,594,797

' GAS BURNER Filed Aug. 13, 1949 3 Sheets-Sheet 2 i ls! INVENTORS RAYMOND 5. H.455

5310914490 MI BUVGHAM ATTORNEY April 1952 R. B. PLASS ET AL 2,594,797

GAS BURNER Filed Aug. 13, 1949 3 Sheets-Sheet 5 NVENTORS RAYMOND B. PLA$S- EDWARD M. Bl/VGHAM 30 BY ATTORNEY Patented Apr. 29, 1952 GAS BURNER Raymond B. Plass, Berkeley, and Edward M.

Bingham, San Rafael,

Calif., assignors, by

mesne assignments, to Ray Oil Burner 00., a corporation of California Application August 13, 1949, Serial No. 110,128

6 Claims.

This invention relates to gas burners and particularly to a gas burner of the horizontal type that may be formed as a part of and used alternately with a rotary oil burner.

In the burning of gas in a horizontal burner, it is essential in order to produce a stable and efiicient flame to effect mixing of the gas fuel with the air required for combustion as quickly and as thoroughly as possible. In large capacity burners, wherein large quantities of gas are admitted to the combustion chamber through relatively limited areas, the gas and air must be mixed either by means of some form of mechanical mixing device or through use of the energy in gas or air under high pressure.

It is customary practice to combine the gas and air in stages by pre-mixing a definite portion of the air, referred to as primary air, with the gas before they are admitted to the combustion chamber and then to allow secondary air in one or more stages to combine with the fuel during. combustion.

Generally speaking, low pressure burners are those in which the fuel is supplied at below 10" water gauge and high pressure burners are those in which the fuel is supplied above 1 p. s. i. The burner with which the present invention is concerned is of the low pressure type in which the motor actuated blower system of a typical horizontal oil burner is employed to supply primary air under pressure for obtaining satis-. factory fuel air mixing. One of the usual practices in burners of this type is to admit gas through a large number of jets or orifices disposed in a circular pattern around the standard nozzle of the oil burner through which air under pressure is admitted so that the gas contacts the outer surface of the air stream issuing from the nozzle, but the mixture of fuel and air under this system is slow and unsatisfactory. Another common practice is to admit the fuel gas to the suction side of the air blower,

charged through the burner nozzle. This latter system constitutes a hazard because of the possible presence of a highly explosive mixture in the blower case sometimes resulting in an explosion and destruction of the case. Furthermore, the quantity of gas which may be taken through the blower without undesirable depletion' of the primary air supply is limited. Another disadvantage of this latter method is that the gas must be supplied to the blower through flexible tubes or hinged connections because it and air and high volume of fuel delivery. A further object of the invention is to provide a gas burner for combination with and for use oil burner of the rotary hazards and disadvantages which have heretofore accompanied such combination burners. The manner in which these objects are carried into practice and further and more specific objects and advantages of the invention are set forth in the following specification wherein a burner embodying the invention is described in detail by reference to the accompanying drawings.

In the drawings:

Fig. 1 is a vertical central section through the mixing cone of a furnace fire box showing a burner embodying the present invention in place,

Fig. 2 is a central horizontal section of the same,

Fig. 3 is a fragmentary section on a central vertical plane of the blower and burner assembly,

Fig. 4 is a section on a central horizontal plane of the same,

Fig. 5 is an enlarged air nozzle of the burner,

Fig. 6 is a side elevation of the same with a portion in section, and

Fig. 7 is a view in rear elevation of the gas manifold removed from the assembly shown in Figs. 3 and 4 and With parts in section.

Referring first to front elevation of the cation with the open end of the conventional mixing or diffuser cone II. A combination gas and oil burner assembly, generally indicated at I2, is arranged to discharge centrally through the diffuser cone H and is supported on a wind box l3 through which the secondary air of combustion is supplied to the burner flame being controlled by adjustable valves or draft doors Id. The secondary air entering through the wind box I 3 fiows to the diffuser cone through the annular space between the outer edge of the cone and the inner portion of the concentrically disposed burner assembly. The combination burner assembly comprises a motor IS, a blower l6 and in the present case, a gas inlet manifold I! secured wind box l3. The motor l and blower l6 are hinged to the gas manifold 11 as by a hinge illustrated at l8 in Fig. 2 so that they may be swung away from the furnace and are held in their operating position by a latch mechanism illustrated at Ill.

The delivery of oil fuel to the burner is accomplished through conventional mechanism with which the present invention is not directly concerned but the arrangement of the blower, the burner nozzle and the means for delivering gas fuel are illustrated in section in Figs. 3 and 4. In these figures, the burner nozzle is shown at 23 as centrally disposed with relation to a refractory cone 2! which backs up the flame emanating from the nozzle and serves as a flame retainer which when heated acts to prevent flame separation or jumping off, sometimes caused by the velocity of the fuel exceeding the rate of propagation of the flame.

The nozzle is supported by the blower casing l6 which contains a fan or rotor 22 secured to and driven by a hollow shaft 23 of the motor Hi. The blower functions to draw air inwardly through a valve controlled opening 24 and to discharge it under pressure through the burner nozzle 23. As is common practice with oil fuel, an atomizing cup 25 is disposed on the end of the hollow motor shaft 23 and receives oil delivered through a fuel tube 26 disposed concentrically with relation to the hollow motor shaft. Th oil is therefore spun off or atomized as it leaves the outer edge of the spinner cup Where it is intercepted by and combined with the air from the to the face of the blower passing between the exterior of the atomizing cup and the interior of the burner nozzle.

During use of th burner with gas as a fuel, the delivery of oil through the fuel tube is of course discontinued and the gas is supplied through the manifold H.

The gas manifold M, also shown in Fig. 7, is a casting which forms an annular chamber surrounding the burner opening in the wind box and adapted to be secured thereto as by bolts or the like. chamber are one or more inlet openings, two being shown at 30 for the connection of pipes which lead to a source of supply of fuel gas. Conventional regulating valve means are of course employed between the gas manifold and the source of supply. Because of the fact that the manifold I! is permanently secured to the front wall of the wind box and need not be disturbed when the burner is swung away from its operating position, the connecting pipes may be rigid. The main body of the manifold l'l comprises spaced walls shown in Fig. 3 as an inner wall 3| and an outer wall 32. The walls are relatively closely spaced but surround the entire burner opening to provide for large volume flow within a flat structure adapted to be disposed between the blower casing and the wind box and at the same time to leave an intermediate space for the admission of air; this space being illustrated at 33. The outer wall 32 of the manifold l1 carries an annular flexible diaphragm 34 secured to it as by cap screws 35 and this diaphragm in turn supports an inwardly directed frusto-conlcal partition 36 which occupies a space between and concentric with the burner nozzle 20 and a surrounding protector plate 31. The position of the partition 36 is such as to form a continuation of the air passage 33 and an annular discharge opening for air from such passage surrounding the burner nozzle, as shown at 33, as well as to form with Communicating with the annular the protector 31 an annular discharge orifice concentric with but spaced from the burner nozzle for gas entering through the manifold 11. This latter annular orifice, shown at 40, is made adjustable by reason of the connection between the diaphragm and the frusto-conical partition 36. As illustrated in Figs. 3 and 4, adjusting screws 4i connect the diaphragm 34 with the member 33 and have a threaded connection with the wall 3! of the manifold ll. The screws 4| have collars intermediate their ends and nuts adapted to be tightened to press together the diaphragm 34 and the member 36. These nuts may be loosened so that upon rotation of the screwsin their threaded sockets the frusto-conical member 36 is adjusted inwardly or outwardly taking advantage of the flexibility of the diaphragm and effecting adjustment of the size and shape of the annular gas orifice 40. In this manner the volume and velocity of the gas entering through the orifice may be controlled. As also shown in Fig. '7, the manifold carries tapped bosses 42 and 43 for attachment of the hinge fittings and latch fittings respectively, by means of which the blower and motor assemblies are supported. It is also provided, as shown at 44, with one or more openings for the disposition of igniting and pilot devices such for example as the gas igniter 45 and spark electrode 46 illustrated in Fig. 4.

The burner nozzle 20, detailed view of which are shown in Figs. 5 and 6, is also modified from the conventional burner nozzle in that it is provided with an annular series of spaced perforations 48 at a point intermediate its ends and fitted with an annular collar 48 with spaced angularly disposed slots 50 corresponding in number and spacing to the orifices 48. The function of the orifices 48 and collar 49 is to receive a large volume of the air discharged by the blower as it passes into the nozzle and direct it outwardly through the perforations 48 in the nozzle and forwardly in a swirling path where it will intercept and mix with the gas fuel entering through the annular orifice 40. The collar 49 may be loosely fitted on the burner tip and secured against rotation thereon as by a set screw shown at 5| so that upon release of the set screw it may be rotated with relation to the burner tip and the areas between the channels 50 will serve as valves to close the orifices 48 when the burner is being used with oil fuel. It is also a relatively simple matter if desired to remove the entire burner nozzle which carries the collar 49 and substitute a conventional nozzle when oil is used as a fuel.

The burner nozzle, as also shown in Figs. 5 and 6, is provided with interiorly disposed diagonally arranged vanes 52 adjacent its outer end which serve to impart a swirling action to the air discharged therethrough. This air, which may be considered a secondary air augmenting the secondary air entering through the wind box will, therefore, have an agitating and mixing effect upon the gas and primary air before and during the initial stages of its combustion.

Because a large portion of the air from the blower passes through the orifices 48 in the nozzle, it enters the mixing chamber in jet-like streams producing a good mixture of primary air gas and also serving to inspirate additional primary air through the passage 33 between the blower casing and the gas manifold l1.

Through the invention disclosed herein, a burner is provided to which a large quantity of fuel gas may be delivered without the usual hazards, without cutting down the quantity of primary air supplied for combustion with the gas, and with assurance that the admixture of gas and air is unusually good. All of this is accomplished without interfering with the operation or complicating the structure of the conventional oil burner and without in any way sacrificing efficiency or desirable operating characteristics of the oil burner.

We claim:

1. A gas burner which comprises a burner nozzle arranged to discharge air under pressure annular discharge areas to increase turbulence during mixture of the gas and air.

2. A gas burner which comprises a burner nozzle adapted to receive air under pressure and to discharge it in an annular direct the air therefrom in spaced jets forwardly over the outer surface of the nozzle, and means to deliver gas in an annular pattern surrounding and concentric to the nozzle.

3. A gas burner which comprises a burner nozzle adapted to receive air under pressure and to discharge it in an annular pattern from within its forward end, said nozzle having a circumscribing plurality of ports for discharging air through its wall, a collar surrounding the nozzle and having slots registering with said ports to direct the air tric to the nozzle, said collar being adjustable by rotation on the nozzle to move its channels out of registry with said ports for closing them.

4. A gas burner comprising a blower which includes a case adapted to be disposed adjacent a furnace wall, a nozzle for directing air from the blower into the furnace. a gas manifold interposed between the blower and the wall and formmeans for directing some of the air from the blower through said passageway in jets to inspirate additional air through the passageway for admixture with gas from said discharge opening. 5. A gas burner comprising a blower which includes a case adapted to be disposed adjacent a nozzle for directing air from the furnace, a gas manifold interposed between the blower and the wall and forming with the blower case an air passageway with an outlet surrounding the nozzle and discharging into the furnace, said manifold having an surrounding the nozzle and disposed between the blower and the furnace, said manifold having spaced walls terminating in spaced frusto-conical sections combining to form an annular discharge RAYMOND B. PLASS. EDWARD M. BINGHAM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

